Change comes fast in the NBA, and even the hottest starts can cool off in a hurry.

At this time a year ago, the Sacramento Kings, Los Angeles Lakers and Houston Rockets were all among the West's top six. Only one of them, the Lakers, ultimately made the playoffs...and they needed the Play-In to get there.

Meanwhile the LA Clippers, who were 11th in the conference at this time last season, wound up with home-court advantage in the first round.

What does that mean for this season's early achievers among teams and players, like the Cleveland Cavaliers, Golden State Warriors and potential scoring champ LaMelo Ball?

We know teams and players don't always finish as well as they start, but at the same time, a month's worth of data is hard to dismiss as flukey. We're going to take a crack at it anyway by sorting suspect starts from those with real staying power.

Cleveland Cavaliers

The Cleveland Cavaliers weren't going to go 82-0, and if you're going to lose after reeling off 15 straight, how better to do it than against the defending champs on the road after nearly erasing a 21-point deficit? But other than knowing the odds of an undefeated season were pretty low, what's not to like about the unblemished, East-leading Cavs?

First of all, this defense is legitimate. Cleveland is among the top 10 in defensive efficiency, a spot it has occupied in each of the previous three years. With Jarrett Allen patrolling the lane and Evan Mobley erasing mistakes everywhere (while also frequently shutting down the most dangerous opposing wing), nothing about the Cavs' work on D is unsustainable.

On the other end, Darius Garland looks like he's back in form after a broken jaw threw his 2023-24 off track. The 25-year-old point guard is back to canning well over 40.0 percent of his threes, has cut his turnovers and looks even better than the player who made his first All-Star team back in 2021-22.

Donovan Mitchell continues to perform at All-NBA levels, Mobley has taken a leap toward stardom and new head coach Kenny Atkinson is getting career-best efforts from the likes of Caris LeVert and Ty Jerome. Isaac Okoro is even hitting 45.7 percent of his threes!

The Cavs are deep, balanced, well-organized and studded with stars. You'd have to go out of your way to nitpick any part of their scorching start.

Verdict: Buy

Ty Jerome, Cleveland Cavaliers

We have to bring the Cavs down to earth a little, and Ty Jerome is the nit we're going to pick to accomplish that.

Jerome is blowing away his career-high effective field-goal percentage of 58.0 percent, set in 33 games he played for the Oklahoma City Thunder in 2020-21, by posting a blistering 64.8 percent figure. His floaters are falling at unsustainable rates, and nobody makes two-thirds of their shots from 3-10 feet or 58.3 percent of their attempts from 10-16 feet with any level of volume over a full season.

If that data is sliced too thinly to drive the point home, we can at least agree that Jerome probably won't keep nailing over half of his three-point shots.

This is still a tremendous breakthrough for the 27-year-old guard, who's well on his way to setting new career highs in games, minutes, points, assists and virtually every volume or efficiency number of his six-year career. Incredibly, Jerome's 18 steals are already approaching his career high of 30 from 2021-22.

But we're still talking about a journeyman reserve who's had some moments over the years but never stayed healthy or productive enough to stick as a rotation fixture. When Jerome cools off, he'll still be a useful backup. He's just not this good.

Verdict: Sell

Golden State Warriors

The longer this goes on, the easier it is to believe the Golden State Warriors can stick as a top-four team in the West on the strength of Stephen Curry, depth and defense.

Steph, playing his age-36 season, is as dominant as ever. He's averaging 28.5 points, 7.9 assists and 6.1 rebounds per 36 minutes while hitting 42.7 percent of his threes. His per-game numbers aren't what they used to be, but that's only because Golden State's league-best bench allows for him to take more rest than he has since 2011-12.

Curry leads the Warriors with just 29.1 minutes per game, part of a rotation that features 12 other players who average at least 11.0 minutes every night.

The absence of a reliable secondary scorer is a real problem, but it might only rear its head in the playoffs. For now, Golden State is firing up enough threes and generating enough transition chances with its frenetic defense to rank among the top 10 in offensive efficiency. That's more than good enough to sustain this level of play, especially with a defense that seems like a lock to stay among the top five all year.

Buddy Hield and Draymond Green may not make nearly half their threes all season, and injuries will eventually eat into the Warriors' depth. If Curry goes down for extended time, it's all over. But this is a team otherwise built to withstand health issues, one that plays a relentlessly aggressive style most opponents aren't ready for.

Verdict: Buy

Phoenix Suns

This isn't so much an outright lack of faith in the Phoenix Suns as it is a statement that, among the teams with the best records in the early going, they're the one with the most red flags.

Start with a negative point differential that says the Suns should have closer to seven wins, not nine, through their first 15 games. As you might suspect, Phoenix's tremendous play in the clutch has a lot to do with its success in the standings. The Suns have a 7-2 mark in clutch games and a plus-14.2 net rating in the last five minutes when the score is within five points. For a reminder of just how fickle and unsustainable clutch stats can be, note that these same Suns posted a minus-5.5 net rating in the clutch and were one of the very worst fourth-quarter teams in the league a year ago.

Kevin Durant looked like a top-five MVP candidate and led the league in minutes per game right up until suffering a calf strain, and Phoenix gets outscored by 4.7 points per 100 possessions when he's off the floor. Any squad that needs its 36-year-old superstar to grind out such massive minute totals is flimsier than it looks.

Phoenix should still be considered a playoff threat, but it won't hang around the West's elite for long.

Verdict: Sell

LaMelo Ball, Charlotte Hornets

If you held the MVP vote today, LaMelo Ball would have to get serious consideration among the top five. Averages of 29.7 points, 6.7 assists and 5.0 rebounds are hard to ignore.

Ball's career-best scoring mark is fueled by a spike from an already high three-point attempt rate and better foul-drawing craft than he's shown at any point in the previous four seasons. He's firing off 12.8 triples per game (in only 33.9 minutes) and hitting 36.1 percent of them, a rate that looked a lot better before he went 6-of-22 across a two-game stretch against the Milwaukee Bucks and Cleveland Cavaliers on Nov. 16 and 17.

His 5.2 free-throw attempts are also a personal best, and Ball (88.2 percent) has always been money at the line.

The Hornets are only 5-8, but they've played virtually the entire year with their top two centers on the sidelines. Ball's impact on that modest record is hard to deny, as Charlotte is nearly 10.0 points per 100 possessions better when he's on the floor.

Skeptics could still point to Ball's start as a standard "good stats, bad team" situation. But his 57.5 true shooting percentage is his best ever and, more broadly, isn't a statistical outburst like this exactly what we should have expected from a player with his career history?

Ball was the Rookie of the Year in 2020-21, made the All-Star team the following season and then essentially lost the subsequent two campaigns to injury. What's so far been an All-NBA-worthy effort is really just Ball picking up where he left off.

Verdict: Buy

Stats courtesy of NBA.com, Basketball Reference and Cleaning the Glass. Accurate through Nov. 18. Salary info via Spotrac, unless otherwise stated.

Grant Hughes covers the NBA for Bleacher Report. Follow him on Twitter (@gt_hughes), and subscribe to the Hardwood Knocks podcast, where he appears with Bleacher Report's Dan Favale.